Relationship of cardiometabolic parameters in non-smokers, current smokers, and quitters in diabetes: a systematic review and meta-analysis

Abstract

BackgroundSmoking is associated with increased macrovascular and microvascular complications in people with diabetes. In addition to other concomitant vascular perturbations, it also seems to influence the cardiometabolic parameters, which may partly explain the accelerated rate of vascular complications in smokers with diabetes. While smoking cessation is advocated as a universal component of the management of diabetes, there is some anecdotal evidence that HbA1c could increase following smoking cessation. The aim of this review is to explore the relationship between smoking and its cessation on cardiometabolic parameters in diabetes.MethodsSearches were conducted on Medline, EMBASE and CINAHL up to March 2016. After screening 6866 studies (Additional file 1), 14 observational studies with a total of 98,978 participants’ with either type 1 or type 2 diabetes were selected for review. Narrative synthesis and meta-analyses were carried out to explore the relationship between smoking and its cessation.ResultsMeta-analysis showed that the pooled mean difference of HbA1c between non-smokers and smokers was −0.61% (95% CI −0.88 to −0.33, p < 0.0001). The difference in LDL cholesterol between non-smokers and smokers was −0.11 mmol/l (95% CI −0.21 to −0.01, p = 0.04). The difference in HDL cholesterol between non-smokers and smokers was 0.12 mmol/l (95% CI 0.08–0.15, p < 0.001). However, there was no statistically significant difference in blood pressure between the two groups. The difference in HbA1c between quitters and continued smokers was not statistically significant −0.10% (95% CI −0.42 to 0.21, p = 0.53). However, a narrative synthesis revealed that over a period of 10 years, the HbA1c was comparable between non-smokers and quitters.ConclusionNon-smokers have a statistically significant lower HbA1c and more favourable lipid profile compared to smokers. Smoking cessation does not lead to an increase in HbA1c in long-term and may reduce vascular complications in diabetes by its favourable impact on lipid profile.Electronic supplementary materialThe online version of this article (doi:10.1186/s12933-016-0475-5) contains supplementary material, which is available to authorized users.

5. Lifestyle Management:Standards of Medical Care in Diabetes—2019

“…Recent data show tobacco use is higher among adults with chronic conditions (164) as well as in adolescents and young adults with diabetes (165). Smokers with diabetes (and people with diabetes exposed to second-hand smoke) have a heightened risk of CVD, premature death, microvascular complications, and worse glycemic control when compared with nonsmokers (166,167). Smoking may have a role in the development of type 2 diabetes (168-171).…”

Review of biomarkers to assess the effects of switching from cigarettes to modified risk tobacco products

“…There is almost no evidence for an association between HbA1c and respiratory disease. A metaanalysis of 14 observational studies with 98,978 participants (with diabetes) found that smokers had significantly higher HbA1c levels than non-smokers (Kar et al 2016). Only sparse information is available on the dose-response relationship between HbA1c and the smoking dose, determined for example by daily cigarette consumption (CPD), pack-years or suitable biomarkers of exposure such as cotinine in body fluids.…”

Corn silk decoction for blood lipid in patients with angina pectoris: A systematic review and meta‐analysis

“…The overall findings should be interpreted in the context of several potential limitations. First, plenty of studies reported lipid profiles are closely correlated with exercise (Igarashi & Nogami, 2019), diet (Chiu et al, 2016), and smoking (Kar et al, 2016). Unfortunately, these variables were not evaluated in most of the studies included, which may confound the overall findings.…”